Title :
Reciprocity based channel compensation for wideband communications in a multipath environment
Author :
Cox, Henry ; Lai, Hung ; Hirano, Michael
Author_Institution :
ORINCON Corp., Arlington, VA, USA
Abstract :
The effectiveness of spread spectrum techniques to achieve low probability of intercept (LPI) communications can be severely degraded in multipath environments which are common in underwater acoustics. The problem of LPI response to a non-LPI interrogation signal is considered. The underlying concept is to use the received interrogation signal to estimate the channel characteristics. The response signal is then precompensated for the estimated channel distortion on the return path so that improved coherent processing gain can be achieved by the interrogator. Several compensation techniques are compared. The sensitivity of channel characteristics to range changes in a typical undersea environment is found to be significant. Techniques for compensation for range changes are discussed
Keywords :
acoustic signal processing; filtering theory; multipath channels; pseudonoise codes; spread spectrum communication; underwater sound; LPI communications; channel characteristics estimation; channel distortion; coherent processing gain; compensation techniques; low probability of intercept; multipath environment; non-LPI interrogation signal; received interrogation signal; reciprocity based channel compensation; response signal; return path; spread spectrum techniques; underwater acoustics; wideband communications; Acoustic distortion; Acoustic signal detection; Degradation; Matched filters; Signal processing; Spread spectrum communication; Transfer functions; Underwater acoustics; Underwater communication; Wideband;
Conference_Titel :
Signals, Systems and Computers, 1993. 1993 Conference Record of The Twenty-Seventh Asilomar Conference on
Conference_Location :
Pacific Grove, CA
Print_ISBN :
0-8186-4120-7
DOI :
10.1109/ACSSC.1993.342586
